Emma blew up 120 balloons for her party. She put them into 10 bunches with the same number of balloons in each bunch. Ho the textbook? Choose the correct answer below. A. \( ? \cdot 120 \times 10 \) B. \( ? \cdot 10=120 \) O. \( 120 \cdot ?=10 \) D. \( 10 \cdot ?=120 \)

Mean typing speed is 90 wpm , with a standard deviation of 18 wpm. Find the probability a randomly elected sample of \( n=49 \) typists has a mean speed of less than 85 wpm .

2. Escriban dos posibles soluciones para cada una las siguientes desigualdades. a) \( 3 x-1>14 \) b) \( x+13 \leq 53 \) c) \( x-25<-5 \) d) \( 0,5-1,5 x \geq-1 \)

(3) Datos: precios (en pesos colombianos) de algunas frutas en un mercado local: \( 1500,2000,1800,2200,2100,1700 \), \( 1900,2300,2400 \)

In \( \triangle \mathrm{ABC} \), if \( \mathrm{AB}=3 \mathrm{~cm} \). and \( \mathrm{BC}=5 \mathrm{~cm} \), then \( \mathrm{AC} \in \ldots \ldots \) \( \begin{array}{llll}\text { (a) }] 3,8] & \text { (b) }[2,8] & \text { (c) }] 2,8[ & \text { (d) }] 2,5[ \\ \text { In the opposite figure : } & \end{array} \)

Determinar el dominio de la siguiente función: \( f(x)=\left\{\begin{array}{r}2 ; \text { si } x<- \\ x^{2}-x+1 ;-1 \\ x-1 ;\end{array}\right. \)